You can purchase compost in packages or bales at most nurseries or local garden centers. Place a 2-3 inch layer on the bare soil in your garden and around the plants, leaving a few inches of space between the plants and the compost. At the end of the growing season dig the compost into the soil to a depth of 8-10 inches and spread a new layer over the top of the bed. Compost will help suppress weeds and slow water evaporation and if you dig it into the soil every year you will eventually turn your garden soil into rich garden loam. Hope you have a great harvest!